2002-01-1916 Electric and Hybrid Vehicle Testing James E. Francfort Idaho National Engineering and Environmental Laboratory Lee A. Slezak U.S. Department of Energy Copyright © 2002 Society of Automotive Engineers, Inc. ABSTRACT Today’s advanced-technology vehicles (ATVs) feature as well as general information about ATVs, such as how hybrid-electric engines, regenerative braking, advanced they work and their histories. electric drive motors and batteries, and eventually fuel cell engines. There is considerable environmental and The Field Operations Program signed a 5-year testing regulatory pressure on fleets to adopt these vehicles, agreement in 1999 with the following group of Qualified resulting in high-risk purchase decisions on vehicles that Vehicle Testers (QVTs): do not have documented performance histories. The Department of Energy’s Field Operations Program tests • Electric Transportation Applications (lead partner) ATVs and disseminates the results to provide accurate • American Red Cross. and unbiased information on vehicle performance • Arizona Public Service (http://ev.inel.gov/fop). Enhancing the fleet manager’s • Bank One of Arizona knowledge base increases the likelihood that ATVs will • Potomac Electric Power Company be successfully and optimally placed into fleet missions. • Salt River Project • Southern California Edison (SCE) The ATVs are tested using one or more methods - • Southwest Airlines Baseline Performance, Accelerated Reliability, and Fleet • Virginia Power. Testing. The Program and its 10 testing partners have tested over three-dozen electric and hybrid electric DOE’s Office of Transportation Technologies (under the vehicle models, accumulating over 4 million miles of Office of Energy Efficiency and Renewable Energy) testing experience. The Program has initiated the manages the Field Operations Program. The Program additional testing of neighborhood, urban, and hybrid works with commercial and government fleets, and electric vehicles and hydrogen-powered vehicles. industry groups to support the testing and deployment of ATVs in today’s evolving transportation market. Test INTRODUCTION procedures are developed jointly with industry stakeholders to measure real-world performance. The The Field Operations Program provides fleet managers Program’s activities comprise four areas: and other potential advanced technology vehicle (ATV) users with accurate and unbiased information on vehicle • Light-Duty Electric Vehicles (EVs) performance. This allows the purchaser to make • Light-Duty Hybrid Electric (HEVs) and Fuel Cell informed decisions about acquiring and operating ATVs. Vehicles Vehicle information is obtained by testing ATVs in • Light-Duty Alternative Fuel Vehicles conjunction with industry partners and disseminating the • Medium- and Heavy-Duty Advanced Technology testing results. The ATVs are tested using three methods Vehicles. - Baseline Performance Testing, Accelerated Reliability Testing, and Fleet Testing. The testing results are disseminated via Program’s Website in the form of The Idaho National Engineering and Environmental vehicle fact sheets, summary reports, and survey results Laboratory manages the first two program areas. These (http://ev.inel.gov/fop). Additional information on the testing activities and the results are discussed below. Website includes testing specifications and procedures, LIGHT-DUTY ELECTRIC VEHICLE TESTING Drive Cycle Range - Kilometers The Field Operations Program, in conjunction with its Average PbA QVT partners, uses several testing methods to validate Average NiMH light-duty electric vehicle (EV) performance. The testing EP I C ( Ni MH) results are discussed by testing method. Ranger (NiMH) EV1 ( Ni MH) EV BASELINE PERFORMANCE TESTING METHODS - S-10 (NiMH) The Field Operations Program has traditionally used two Baseline Performance testing methods, EVAmerica and RAV4 ( NiMH) Pomona Loop testing. Ranger ( PbA) Chev S-10 (PbA) EVAmerica Testing Results - The EVAmerica testing is EV1 ( P bA ) conducted by Electric Transportation Applications on RAV4 ( PbA) closed tracks and dynamometers and the results are highly repeatable.1 The test parameters include Solect ria Force (NiMH) acceleration, three types of range tests, gradeability, Solect ria E10 (PbA) handling, charging, maximum speed, braking, and 0 20 40 60 80 100 120 140 160 180 200 220 240 minimum safety standards that the vehicles must meet. Figure 2. EVAmerica individual testing results for SAE The Program and its testing partners have conducted J1634 drive cycle tests. (Not all vehicles shown). EVAmerica Baseline Performance testing on 21 vehicle models since 1994. Test vehicles include the Chevrolet The 1998 results were driven by the nickel-metal-hydride S-10, Chrysler EPIC, Ford Ranger, General Motors EV1, (NiMH) equipped EV1 from General Motors. The EV1 and Toyota RAV4. These vehicles were equipped with has the highest test results to date, going 356 km in the nickel-metal-hydride (NiMH) battery packs. The test 72-km/h constant speed test and 259 km in the 97-km/h results provide a good characterization of vehicle constant speed test. The two pickups tested during 1999 performance. The testing has documented range were also equipped with NiMH batteries and they increases of up to 150% when comparing the 1998 test averaged 143 km for the drive-cycle test, 198 km in the vehicles to the 1994 test vehicles (Figure 1). The 1998 72 km/h constant speed test, and 130 km in the 97-km/h results include a drive-cycle2 range of 225 kilometers constant speed test. The 1999 results did not increase (km) for the General Motors EV1 (Figure 2). (For all compared to the 1998 tests; vehicles other than the EV1 classes of EVs, the basis for drive cycle dynamometer with NiMH batteries could not replicate the 1998 results. testing is SAE J1632). The average annual acceleration tests (performed at Driving Cycle Range - Kilometers 50% state-of-charge) show an overall increase in vehicle performance (Figure 3). The average time to accelerate 18 0 . 0 from 0 to 80 km/h has decreased from 24 seconds 16 0 . 0 Acceleration 0 to 80.5 km/h (50% SOC) - Seconds 14 0 . 0 12 0 . 0 30.0 10 0 . 0 80.0 25.0 60.0 20.0 40.0 20.0 15. 0 0.0 10 . 0 1994 1995 1996 1997 1998 1999 5.0 Figure 1. EVAmerica drive cycle (SAE J1634) 0.0 19 9 4 19 9 5 19 9 6 19 9 7 19 9 8 19 9 9 average (mean) annual testing results. All three of the range tests (Driving Cycle, Constant Figure 3. Mean EVAmerica acceleration Speeds at 72 and 97 km/h) exhibit similar trends – an testing results. overall continuing improvement in EV performance. The recorded during 1994 to 12 seconds for the 1999 test 1997 decreases in range can be attributed to the type of vehicles. The lead-acid EV1, tested during 1996, had a 0 vehicles tested that year. Both of the 1997 test vehicles to 80-km/h acceleration time of 6.7 seconds at a 50% were pickups, with lead-acid batteries and high payloads, state-of-charge. At 100% state-of-charge, the EV1 intended for use in utility types of fleet applications. accelerated from 0 to 80 km/h in 6.3 seconds. The single most important factor for increasing vehicle Table 1. Definition of the Urban and Freeway Pomona range is the amount of kWh stored in a vehicle’s battery. Loop testing scenarios. (Min – minimum, Max – Increasing the kWh can be accomplished by increasing Maximum, A/C – air conditioning) the number of batteries onboard or using a higher- capacity battery technology. NiMH batteries were used Urban Loops on seven vehicles to increase range. The higher specific UR1 Minimum payload, no auxiliary loads energy of NiMH batteries is evident when looking at Figure 4. During 1995, two out of the three test vehicles UR2 Min payload, A/C high, headlights low, radio on were equipped with NiMH batteries, as were all five UR3 Maximum payload, no auxiliary loads vehicles tested during 1998 and 1999. During 1994, 1996, and 1997, lead-acid batteries were used in 12 of UR4 Max payload, A/C high, headlights low, radio on the 13 vehicles tested (one 1994 vehicle used nickel-iron Freeway Loops batteries). The watt-hours per kilogram of the two NiMH battery packs used in the 1999 test vehicles is 130% FW1 Minimum payload, no auxiliary loads greater than the lead-acid battery packs in the two 1997 FW2 Min payload, A/C high, headlights low, radio on test vehicles. FW3 Maximum payload, no auxiliary loads Drive Cycle specific Energy - Wh\ Kg FW4 Max payload, A/C high, headlights low, radio on 60 The Pomona Loop testing results displayed in Figure 5 50 include the minimum and maximum testing results for all eight Urban and Freeway tests. The graph ranges 40 include the four testing scenarios for each Loop. 30 20 Po mo na Lo op M inimum and M aximum R ang es 10 0 Rang er PbA 19 9 4 19 9 5 19 9 6 19 9 7 19 9 8 19 9 9 Honda EV Plus EV 1 PbA Figure 4. Average (mean) specific energy (watt- EPIC PbA hours per kilogram) of the EVAmerica test S-10 Delphi vehicles. S-10 NiM H Nissan A lt ra Pomona Loop Testing Results - The Field Operations EPIC NiM H Program also supports the Urban and Highway Pomona Ranger NiM H Loop Baseline Performance testing conducted in Southern California. In addition to confirming EVAmerica RAV4 Inductive test results, the Pomona Loop testing sometimes S-10 Panasonic provides access to vehicles that are only available in EV1 Panasonic PbA California. In contrast to the “closed track” nature of the RAV 4 Cond uct ive EVAmerica Baseline Performance tests, the Pomona 0 20 40 60 80 100 120 140 160 180 200 Loop tests are performed on Southern California urban Kilomet ers streets and area freeways. Some fleet managers prefer the nature of the Pomona Loop on-road testing rather than the dynamometer evaluation of the EVAmerica methodology.